MongoDB Interview Question & Answers

MongoDB Interview Question & Answers

By giving expert level trainers from Spiritsofts are MongoDB interview questions & Answers can develop your carrier & knowledge to find the right job in a good MNC’s, doesn’t matter what kind of company you’re hired.

What is MongoDB?

Mongo-DB is a document database which provides high performance, high availability and easy scalability.

A replica set is a group of Mongo instances that host the same data set. In replica set, one node is primary, and another is secondary. From primary to the secondary node all data replicates.

How you can inspect the source code of a function?

To inspect a source code of a function, without any parentheses, the function must be invoked.

What are indexes in MongoDB?

Indexes are special structures in MongoDB, which stores a small portion of the data set in an easy to traverse form. Ordered by the value of the field specified in the index, the index stores the value of a specific field or set of fields.

How can you see the connection used by Mongos?

To see the connection used by Mongos use db_admin Command (“connPoolStats”);

What is the syntax to create a collection and to drop a collection in MongoDB?

Syntax to create collection in MongoDB is db. create Collection(name,options)Syntax to drop collection in MongoDB is db.collection.drop()

How replication works in MongoDB?

Across multiple servers, the process of synchronizing data is known as replication. It provides redundancy and increase data availability with multiple copies of data on different database server. Replication helps in protecting the database from the loss of a single server.

What is the role of profiler in MongoDB?

MongoDB database profiler shows performance characteristics of each operation against the database. You can find queries using the profiler that are slower than they should be.

Explain what is GridFS in MongoDB?

For storing and retrieving large files such as images, video files and audio files GridFS is used. By default, it uses two files fs.files and fs.chunks to store the file’s metadata and the chunks.

What is “Namespace” in MongoDB?

MongoDB stores BSON (Binary Interchange and Structure Object Notation) objects in the collection. The concatenation of the collection name and database name is called a namespace.

Mention what is the command syntax for inserting a document?

For inserting a document command syntax is database.collection.insert (document).

What is the command syntax that tells you whether you are on the master server or not?

Command syntax Db. is Master() will tell you whether you are on the master server or not.